1. A person that consistently responds to email in the most arrogant and / or demeaning way possible in as few words as possible, but when in face to face interactions are kind and considerate.

2. A person that sends an email response equivalent to one word for every sentence received.

Example #1. I was surprised by what a nice guy John Doe was, because he is such an "email dicknob".

Example #2. Original Email Message:
John Doe, it was great to meet with you today. I enjoyed the opportunity to discuss our potential for partnering together in this exciting joint venture. I know that we have the right plan in place, and look forward to our long term success.